Hey,
I'm going for something very similar in Portland or the surrounding areas so I've spoken with a few lenders about almost exactly the same thing (minus the father-in-law part).
I recently put an offer in on a HUBZU property on 73rd and Halsey. It was a duplex at around 265k, which is unheard of in Portland's market, specially that area, because things move fast and usually go for higher than ask. I was splitting everything down the middle with an investor who knows contracting and I'm a realtor - good team! ;) We ended up loosing the auction and our income history wasn't long enough (2 full years)
Keep in mind that when you're going with FHA loans:
- Both you and the 'co-borrower' must promise, on paper, to use the property as your primary residence. So, your mail goes there.
- The offer becomes way less attractive than any other offer that is a conventional loan because the seller assumes that you have less cash lying around so there's a higher chance of the deal falling through due to failure to finance (which means you get your earnest money back, generally).
Consider saving up for a conventional or 'Rehab' loan which looks much more attractive than FHA and is more popular in this market. My first move would be to call up a lender and talk to them about what your planning, get the specs and get a preapproval so you know what number you're working with and go from there.
If you need s good lender out here send me a message and I'll connect you!
I hope that helps!